Here is everything you need to know about food in a 3-Part Pyramid
Whole Foods First: If you are eating as close to nature as possible, always going to the least processed version of any food, you are doing 90% of the work
Nutrient Density: Within your whole foods try to eat the groups that give you the most nutrition with the lowest caloric load. Think above ground vegetables over high starch foods, and berries over bananas type of stuff
Protein Ratio: Lastly, within your whole, nutrient dense food selections, the icing on the cake is getting the most protein you can per calorie.
If you are filtering your meal decisions through this frame of thought you will almost always be making great food decisions.